Objective To detect the level of serum hyaluronic acid (HA) and insulin-like growth factor -1 (IGF-1) in thyroid-associate ophthalmopathy (TAO) patients and to provide experimental evaluation of the activity of TAO. Methods 55 cases of OTA patients with normal thyroid functions were involved. The patients based on Clinical Activity Score (CAS) were classified to activity stage group ( CAS≥4, 30 cases) and resting stage group (CAS＜4, 25 cases). 36 people without TAO and thyroid-associated disease were enrolled into the control group. The levels of serum HA and IGF-1 in patients and healthy controls were measured by radioimmunoassay. The receiver operator characteristic curve was used to evaluate the diagnostic value for the activity of thyroid-associate ophthalmopathy. Results The serum HA and IGF-1 levels in active stage group were significantly higher than that of resting stage group and control group (P＜0.01). The levels HA and IGF-1 in active stage group were 2.38 and 2.82 times higher than that of in resting stage group, and 2.80 and 3.09 times higher than that of in the control group respectively. The serum HA and IGF-1 levels were increased with the increase of severity of TAO (P<0.05). The receiver operator characteristic curve (ROC) showed that the area under curve of HA and IGF-1 from TAO patients were 0.933 and 0.927 respectively. The average sensitivity and specificity of HA and IGF-1 for diagnosis the activity of TAO were 93.8%, 86.1%, 91.6 % and 84.1% respectively. Conclusion The serum levels of HA and IGF-1 are correlated with the activity of thyroid- associated ophthalmopathy. The serum HA and IGF-1 might be involved in the development of thyroid-associated ophthalmopathy. The serum HA and IGF-1 could be used as index for providing experimental evaluation of the activity of TAO.